The template hierarchy applies here, regardless of if you used CPTUI or not.
https://developer.ww.wp.xz.cn/themes/basics/template-hierarchy/
Is there a way to use different templates for parent and child posts? Right now my child pages are still looking for another level of child posts, same as the parent pages, and I want to disable this for child individual pages.
ceefitz, I wager you could work something out for this with the details at https://developer.ww.wp.xz.cn/themes/basics/template-hierarchy/#single-post
There’s no Template selection dropdown for custom post types, like there are for pages, and that’s something we can’t control.